Combination muffler and air heater



ylime 7, 1932. .1. T. VAN IDERsTlNE COMBINATVION MUFFLER AND AIR HEATER Original Filed May 26, 1926 Patented June 7, 1932' PATENT OFFICE JOHN T. 'VAN IDERSTINE, 0F CHICAGO, ILLINOIS COMBINATIN MUFFLER AND AIR HEATER Application led May 26, 1926, vSerial No.

This invention relates to a combination muiiler and air heater for automobiles and it has particular relation to a combination muffler and air heater which comprises a cylin- 6 der having a conical-shaped forward end, an inlet and an outlet for the exhaust gases aty the rear end thereof, and a jacket surrounding said cylinder in a spaced-apart relation for confining air to be heated by the exhaust l gases passing through said cylinder.

i Heretofore ordinary muier construction comprised a cylinder having a series of baffle plates against which the exhaustsgases would strike, or, a series of chambers having restricted openings through which the exhaust gases would pass, whereby, in either instance, the gases were compressed and the explosions of the engines were silenced.

The present invention teaches the use of a zogcylinder having an inlet and an outlet at the rear end of said cylinder, the outlet pipe to be carried through the cylinder to a point near the forward end thereof. The gases upon entering the cylinder are forced forwardly therethrough and as the outlet pipe is of a substantially smaller diameter than that of the cylinder, a restriction in the ow of the gases occurs as they are introduced into the outlet pipe, thus causin a sufficient compression to silence the soun of the explosions of the engine. It will, moveover, be apparent that the circuitous passage of the exhaust `gases provides a more eiiicient heating surace of the cylinder wall.

The jacket surrounding the muiier is so constructed as to be inexpensive in manufacture and eiiicient in operation. This jacket comprises three nested cylinders, the outer and inner cylinders being of metal, while the 4 third is of insulation and Vis interposed between said first two cylinders. The elements of the jacket are secured together by means vof rivets so arranged that the heads thereof serve as the means for holding the jacket in spaced-apart relation with the muiiler and, moreover, allow for a small and uniform air passage therebetween.

In order to facilitate the introduction of fresh air into the air passage between the cylinder and its jacket, the forward end of the 111,687. Renewed September 29, 1931.

cylinder is cone shaped. This novel method of shaping the forward end of the cylinder also serves to center the exhaust. gases within the cylinder and to introduce the gases into the end of the outlet pipe from which point they are finally exhausted.

In the ordinary type of heater there is danger that the poisonous gases of the exhaust may escape into the heater and be admittedy into the car because of the many fittings and joints within the heating surface which are liable to leak.

The present invention reduces this danger of escaping gas to a minimum by having the cylinder project a sufiicient distance beyond 05 the surrounding jacket which forms the air passage so that all exhaust connections are on said projection and remote from the air passage.

A further feature of this invention is the auxiliary outlet pipe connected to the lower rear end of the muffler and controlled by a valve. When the engine in an automobile is running at a high rate of speed, the exhaust gases may create a compression so great that they will materially affect the efficiency of the engine. It is necessary to relieve this excess compression in order to increase the engine power and, therefore, an automatic valve controlr is provided which is adapted to relieve the gases before being compressed in the cylinder.

One of the objects of this invention is to provide a combination muffler and air heater of a design to be inexpensive in manufacture and efHcient in operation. i

A further obj ect of the invention'is to provide a combination muilier and air heater in which the exhaust connections are at a point remote from the air passage.

A further object of this invention is to provide a combination muffler and air heater in which the inlet and'outlet are at the rear end thereof.

A further object is to provide a combina- 'tion muffler and air heater adapted to' aut0 matically control the amount of compression within said muffler and heater.

Further objects and advantages will be apparent from the following descriptionl when l0 read in connection with the accompanying drawing, in which drawing:

Figure 1 is a sectional view through the chassis of an automobile showing this device p attached thereon;

Fig. 2 is aV lateral section through the device;

Fig. 3 is a section on the line 3 3 of Fig. 2; and

Fig. is a lateral section through the valve construction.

Referring more particularly to the drawing, the combination muffler and air heater 10 are shown mounted on an automobile chassis and comprises a cylinder 11 and a jacket 12 in a spaced-apart relation with the cylinder. The engine 13 of the automobile has an exhaust manifold 14 which is connected to the rear end of the cylinder by means of the exhaust pipe 15. A conduit 16 is connected to the jacket 12 and extends to a register 17 within the passenger compartment of the automobile.

Exhaust gases are emitted from theengine 13 and are passed through the exhaust pipe 15 to the cylinder 11 where the noise accompanying the explosions of the gases in the engine is silenced and the gases allowed to escape. Fresh air is drawn into the chamber 18, afforded by the spaced-apart relation of the jacket 12 with the cylinder 11, and is heated by the exhaust gases passing through the cylinder. The heated airis then admited `into the passenger compartment bymeans of the conduit 16 and the register 17.

` The cylinder 11 has an inlet 19 at the rear i end thereof, said inlet being connected to the exhaust pipe 15. An outlet pipe 2O projects through the rear end of the cylinder 11 and extends therethrough to a point near the forward end. It is preferable to have the pipe of a substantially smaller diameter than that of the cylinder 11 in order that the gases, when forced into the cylinder, may be restricted in their flow upon entering the smaller outlet pipe and thereby cause a compression suflicient to silence the sound of the explosions of the engine. 'It is also preferable to have the forward end of the cylinder cone-shaped to center the flow of gases in order to introduce these gases into the end of the outlet pipe 20.

In order that the restriction of gases be sufficient to cause the necessary compression, a .bathe plate 21 is provided having a plurality of apertures 22 formed by cutting adjacent spaced-apart slits, after which thematerial between the slits is deformed to'extend forward and beyond the plane of the surface of the plate. The gases must-pass through these restricted. openings and receive an `initial compression, the latter to be furthered by the hereinbefore described toom#f pression produced by the outlet pipe 20.

rIfhe jacket 12 surrounding the cylinder 16 comprises three nested cylinders 12, 12b and 12. The outer cylinders, 12ab and 12C, are of metal, and the third cylinder, 12b, is of insulation and interposed between the two outer cylinders. The three cylinders are secured together lby means of rivets 23, the heads of which afford a means for holding the jacket 12 in a spaced-apart relation with the cylinder 11 and also provide a chamber 18. The lower half of the cylinder 12a is carried forward and splayed to form a shield member 24 which extends several inches beyond the apex of the cone of the cylinder 11. This shield member 24 prevents water from splash ing on the exposed end of the cylinder 11. If water were permitted to contact with the end of the cylinder, it would absorb heat therefrom which would be carried away inthe form of steam.

When the automobile is in motion, fresh air is forced into the chamber 18 where it is heatedI by the heating surface of the cylinder 11, and the heated air is then passed through the conduit 16 into the-register 17 within the passenger compartment of the automobile. The conical-shaped forward end of =the cylinder 11 facilitates the introduction of fresh air into the chamber 18 and is an essential feature of this invention since the (chamber is very small. sage provides for a close contact with the heating surface and as the open end of this chamber'faces the direction of travel of the automobile, a sufficient amount of air is obtained. if

vThe cylinder 11 is formed preferably of a seamless tubing fand its rear end projectssufficiently beyond the end of the jacket 12 to permit of the connections for the inlet and outlet to be made at a point remote from the heating chamber. This construction provides that the entire heating surface is without joint or opening through which gases might'escape into theheater and thence into the car. J

Then the engine of the automobile is running at a high rate of speed, the exhaust gases may create a compression so great that it will materially affect the efficiency of the engine. In order to relieve this excess compression, an auxiliary outlet pipe 24:is provided which is vconnected to the This small pascylinder 11.at the rear end thereof. A clo ,spring member 27. When the pressure of the exhaust gases exceeds a predetermined amount, the tension of thespring 27 is overcome and the closure 25 is forced open and the exhaust gases arepermitted to escape, thereby relieving the excess compression within the cylinder 11.

It is apparent from the foregoing description that the circuitous fiow of exhaust gases through the cylinder 11 by means of the inlet and outlet being disposed on the rear end thereof greatly increases the healting efficiency of the cylinder, and that the construction of the cylinder is such as to relieve the danger of deadly exhaust gases being transmitted into the car; and further, that the conical-shaped forward end greatly facilitates the introduction of the exhaust gases into the outlet pipe and the introduction of fresh air .into the chamber; and that, therefore, this method of reducing the flow of exhaust gases simplifies and reduces the expense of production to a minimum. f

While but a single embodiment of this invention has been herein described and shown, it is to be understood that this invention is not to be limited to the exact detail and structure disclosed herein, since various ,other forms will be apparent to one skilled in the art and consequently this invention is to be limited only by the scope of the appended claims and the prior art.

` I claim:

l. In combination with the exhaust pipe of an internal combustion engine of an elongated cylinder having a cone shaped forward end and an inlet in tle rear end there- .of connected to said exhaust pipe, an outlet pipe .entering said cylinder at the rear end thereof and continuing therethrough to a point adjacent the apexof said cone shaped forward end so that the area between the periphery of the inner end of said outlet pipe and the closest wall of said cone shaped forward end is not greater than the cross sectional area of said outlet ipe, said" cone shaped forward end being adiapted -to gradually compress and center the exhaust gases in said cylinder and thereby facilitate the introduction of said exhaust gases into said outlet pipe. y

2. In combination with the exhaust pipe of an internal combustion engine, of an elongated cylinder having. a cone-shaped forward end and an inlet in-therear end thereof connected to said exhaust pipe, an outlet pipe, entering said cylinder at the rear end thereof and continuing therethrough to a point adv jacent the apex of said cone-shaped forward endisaid outlet pipe being of a substantially smaller diameter than that of said inlet pipe causing a restriction in the flow of the exhaust gases thereby producing a compression to silence the sound of the explosions of said engine. v

3. In combination with the exhaust pipe of an internal combustion engine, of an elongated cylinder having an inlet in the rear end thereof connected to said exhaust pipe, an outlet pipe entering said cylinder at ,the rear end thereof and continuing therethrough to a point adjacent the forward end, said outlet pipe being of a substantially smallei diameter than that of said inlet pipe tl"s causing a restriction in the flow of the exhaust gases, thereby. producing a compression to silence the sound of the explosions ofsaid engine, and an auxiliary outlet pipe connected to said cylinder, said auxiliary outlet pipe being automatically controlled to permit of the escape of exhaust gases after a predetermined pressure in said cylinder has been reached.

4. In combination with the exhaust pipe of an internal combustion engine, of an elongated cylinder having a cone-shaped for- Ward end and an inlet in the rear end there-` of connected to said exhaust pipe, an outlet pipe entering said cylinder at the rear end thereof and continuing therethrough to a point adjacent the apex of the cone-shaped forward end, said outlet pipe being of a smaller diameter than that of said inlet pipe and means in said cylinder for restricting the flow of exhaust gases therethrough, said cone-shaped forward end adapted to receive and to vcenter the exhaust gases thus restricted and facilitate the introduction thereof into said outlet pipe.

In witness whereof, I have hereunto subscribed my name.

JOHN T. VAN IDERSTINE. 

